I use the oem filter and mobil bike specific synthetic 10/40 oil. The stock filter is about the best around, suzuki recommends running it for 36 months or every 3rd oil change on some model bikes. Nobody else recommends running their filter at those intervals. Plus its one of the best constructed. And the mobil bike oil you can run for extended changes with no reduction in shifting quality like you get with alot of other oils. Great combo imo
I change my oil every 8k miles or 2 years
And I've always heard from everywhere (all over the net, local and online shops etc) stock clutch plates are the best for durability and dependability.
There's a forum here
Bob Is The Oil Guy - Forums powered by UBB.threads™ A good portion of the forum members (including bike riders) test their oils after different length oil change intervals and post up the results. You'd be amazed how long a good synthetic will go before it starts to break down